The thimble clevis is applied as interface fitting to connect the guy grip to dead-end insulator or U clevis. The unique design thimble clevis is widely used on pole lines, overhead lines, and transmission tower lines.

The thimble clevis is hot-dip galvanized casting iron or formed steel thimble with many kinds of structures. The thimble clevis is designed with a smooth internal contour to burden the stress concentration on the guy grip loop. The complete set includes casting thimble clevis body and bolt & nut. The bolt is to lock the U clevis and ball socket when completing the installation.

To apply the different spans of the tower or pole, there are 40kn,70kn,120kn, and 160kn thimble clevis to assemble with the preformed tension clamp. If the present thimble clevis structure is not what you want, QUAN PHAM can make thimble clevis according to your drawing or specification.

QUAN PHAM hopes to be your next partner, contact us now!

Thimble Clevis: The Complete Guide

Thimble clevis is a highly important pole line hardware accessory for all your pole line, transmission tower lines, and overhead line needs.

Before you can use this hardware accessory, you need to know about it.

Here, I will provide you with all the information you need.

As you come to the end of reading this guide, you will know why you need thimble clevises, what they are, the process of manufacturing, how to have it installed, types of material, etc. – I will have everything covered in this guide.

Let’s move on and enjoy it.

What is a Thimble Clevis?

Have you ever seen this hardware accessory before?

Thimble Clevis

Thimble Clevis

As the figure above shows, a thimble clevis is designed to include a steel pin that connects it through insulator eye.

It also safeguards it with a humpbacked cotter key.

Its unique design is used mostly on overhead lines, pole lines, and transmission tower lines.

These accessories come in different types for virtually any application.

I will talk about that later in this guide.

For now, let’s look at something even more interesting.

1. Ductile Iron Thimble Clevis

Drawing of ductile iron thimble clevis

Drawing of ductile iron thimble clevis

2. Aluminum thimble clevis

Mostly this thimble type is packaged or provided with some additional components like hex head bolts, nuts, and cotter.

The cotter pin is mostly made of stainless steel.

Its hardware material is hot dip galvanized steel.

Its body is mostly of hot dip galvanized and ductile iron materials.

3. Ultimate strength thimble

Thimble Clevis Thimble clevis

Normally, you will find thimble clevis equipped with nut, bolt, and cotter rather than clevis bolt.

Below is a perfect example.

Thimble clevis

Thimble clevis – Photo courtesy: MacLean Power Systems

Ultimate strength clevises have these features:

  • They are used for normal dead ending and normal duty guying cable applications.
  • They are used for wire grips and bails where 1-1/2 wire seat diameters are needed.
  • They also include integral side, pulling eyes to make easy tensioning guy wire or conductors.

Why You Need Thimble Clevis

Okay, so you know what a thimble clevis is.

However, you have no clear idea about why you need it.

When you know why you need a thimble clevis, it becomes your first step to the application’s success.

The thimble clevis can be applied as an interface fitting.

This is done to link guy grips on dead end insulators or U clevis.

Its unique design is mostly used on overhead lines, pole lines, and tower lines.

Manufacturing Process of Thimble Clevis

The process of making thimble clevis is simple and straight forward.

First, you must have a technical drawing for the thimble clevis.

This is where you will have your dimensions and size.

From here, you can cast or form the material to the appropriate shape and size.

But, you don’t stop there.

You must proceed to improve the performance of the thimble clevis.

And, that brings us to yet another fundamental process.

It is important for you to know that thimble clevis is hot dip galvanized casting iron or formed steel thimbles.

It is made with smooth internal contours to weigh the stress absorption on guy grip loops.

When you purchase a thimble clevis, it comes complete with casting thimble clevis body, bolt, and nut.

How to Install Thimble Clevis

This is a very important part of purchasing thimble clevises.

Fortunately, installing thimble clevises is very easy.

This means that you do not need to struggle at all in having installations done.

  1. Always begin by making sure all bolts and nuts are available. This is needed so that you do not begin the installation process only to realize they aren’t in the box with the thimble clevis.
  2. Assemble with the preformed tension clamp.
  3. Loosen the bolt that tightens or closes the opening.
  4. Have the steel pin linked through the insulator eye.
  5. Have it secured later with a humpbacked cotter key.
  6. Have the wire seat diameter checked. It is needed to aid cables, bails, and wire grips to have their shape maintained.
  7. Insert the right hooks into the pulling eye area to help tension conductors or guy wires.
  8. Lock the U clevis and ball socket with the bolt to complete the installation.
  9. Make sure it is always tight when fastened to prevent accidents due to lose grips.

Also, you need to the following details about installing thimble clevis:

To have different spans of poles or towers applied, you can find different types of thimble clevis.

They must be chosen rightly to ensure assembling with the preformed tension clamp is easy.

You also need to know that, installing of thimble clevis will differ from one project to the other.

Different methods of application will arise depending on the job at hand.

Technical Specifications of Thimble Clevis

Thimble ClevisSide view of thimble clevis

· Dimensions

You can find thimble clevis coming in many dimensions.

You need to be aware of what you need in order to choose the right types.

For your own good do not rush in making such choices.

You can find out the different dimensions a particular manufacturer or supplier has.

If you will need them you can then purchase them.

· Weight

Just as dimensions differ, weights also differ.

Since they can be made to suit specific purposes and client orders, the weights always vary.

· Types of Material

The body of thimble clevis is made of ductile iron, aluminum alloy or hot dip galvanized.

Ensure you go for high-quality material.

Its hardware is made from hot dip galvanized steel.

Cotter pin is made from stainless steel to make it strong and prevent easy breaking.

· Breaking strength

It is very difficult to see high-quality thimble clevises breaking.

Due to the best materials used in making them this unlikely happens.

Generally, its strength may be 40kn, 70kn, 120kn and 160kn.

Always make sure the level of strength is one thing you can be assured of.

I believe you might have had issues in the past with pole line hardware accessories.

This is why you need to purchase the right strength levels depending on your project at hand.

· Design

It is designed with smooth internal contours to load stress concentrations on guy grip loop.

Most of them have a unique eye and is shaped in an oval way.

Besides, they feature a box with the body, bolt, and nut.

It can include some other components depending on your order.

· Clevis Opening

It is always important for you to open thimble clevises the right way.

Rushing to open it with force can lead to some problems when you decide to use it later.

Always make sure you loosen the nut and open the clevis with ease.

Why customers choose thimble clevises from QUAN PHAM?

1. Before packing, the QUAN PHAM QC does the breaking load test on each patch. The test samples are stochastic. The sample percentage is 1:100.

2. All the thimble clevises are selected twice, to reject the piece which is non-standard.

3. QUAN PHAM offers a one year warranty, if there is any quality problem, the thimble clevises can be rejected by the customer.

FAQs on Thimble Clevis

thimble clevisTop view of thimble clevis

I believe there are many questions and doubts you have on your mind.

Day in and out, there are many questions I receive from many people.

Well, in this part of the guide I will be answering a few questions to help guide you.

Let’s get to it:

Should I use any type of thimble clevis for my project?

No matter what project you are undertaking, you’d better use the right material body thimble clevis. Aluminum thimble clevis should be used on the right power lines, poles, and so on.

Can I obtain lower grade thimble clevis?

It is very easy to obtain lower grade thimble clevises, lower graded thimble clevises will cost you less from the start, but that is not what you might get after the job is done.

If you do not want to face accidents after using them, you should search for higher grade thimble clevises for an amazing experience.

How to know what I am purchasing?

You need to check the different pictures and drawings of thimble clevises online. That gives you an idea and helps you to make your purchasing decisions easier.

How much will I spend on thimble clevises?

Due to the large market online, you will always have alternatives in prices.

You just need to have everything done ideally as it is needed so that you buy the best type.

Remember, cheap thimble clevises should not be your ideal choice.

Also, do not go in for overly priced brands as well.

Reasonable pricing and quality should be it for you.

Do I get a warranty when I buy thimble clevis?

Here warranty is available for all pole line hardware accessories, not all of the suppliers and manufacturers will give such warranties.

Note, good manufacturers and suppliers will make sure you have at least a 1-year warranty.

The warranty stands to show how much you can trust the product you are buying, it is one thing that should help you decide which company to make your purchases.

What to do if I cannot install thimble clevis on my own?

It is always good for you to try to install it on your own.

However, if you realize it is taking forever, call in an expert, they will get the job done with ease.

Most of them do not charge much for their services, do not have doubts about calling them, just make sure they are professionals indeed.

Why is the thimble clevis broken after falling?

Thimble clevises are made of strong materials and not to easily break.

So, if they are broken after falling, there may be a problem with whom you made your purchase.

Some thimble clevises fall that will ideally leave some impact on this hardware accessory, it should be a total breakage of the accessory.


It is very clear now through this guide how important thimble clevises are.

Basically, you need to buy a reliable thimble clevis and from the right manufacturer.

I am very certain with this simple guide; you will find ideal and realistic solutions to your problems.

Here at QUAN PHAM, we make it our goal to meet all your pole line hardware needs.

Contact us now, and our team of experts will provide you with all the help you need in purchasing and using thimble clevises.

Product Specifications : Thimble Clevis 
Code Breaking strength(kn) WEIGHT(KG)                                          SIZE(mm)
JYTC-05-B 50 0.65 M16 38 18 43
JYTC-07-B 70 0.85 M16 38 22 55
JYTC-10-B 100 1.00 M16 50 22 62
JYTC-12-B 120 1.1 M16 50 22 62
JYTC-16-B 160 1.6 M16 60 25 64